Moving mask for shielding articles

ABSTRACT

Apparatus and method for shielding a portion of an article in an article treatment zone. A plurality of articles are transported in single file through an article treatment zone. The articles may be glass containers, and the treatment material may be a metallorganic decorative spray. In the article treatment zone, mask means closely engage a portion of the article to shield or protect a portion of the article from contact by the treatment material. The mask means may take the form of counterrotating, complementary pairs of shield members which are cammed into engagement with the article at the treatment zone entrance, move in synchronism with the article through the treatment zone and are cammed out of engagement with the article at the exit of the treatment zone.

United States Patent 1 Johnson MOVING MASK FOR SI-IIELDING ARTICLES [75] Inventor: John R. Johnson, Toledo, Ohio [73] Assignee: Owens-Illinois, Inc., Toledo, Ohio [22] Filed: June 25, 1973 21 Appl. No.: 372,974

[51] Int. Cl. B05c 11/14 [58] Field of Search 118/301, 503,504, 213, 118/406, 63; 117/38; 198/162 [56] References Cited UNITED STATES PATENTS 1,830,114 11/1931 Kenney 118/301 X 2,505,063 4/1950 Palermo 118/301 2,600,161 6/1952 Fouse 118/301 X 2,740,375 4/1956 Diehl ct al. 118/505 X 3,143,269 8/1964 Van Eldik 198/162 X 3,296,999 l/1967 Gamble 118/301 X 3,462,001 8/1969 Boyce 198/165 X 3,713,862 l/l973 Winkless 117/38 X Primary Examiner-John P. McIntosh Attorney, Agent, or Firm-Steve M. McLary; E. .1. Holler [5 7 ABSTRACT Apparatus and method for shielding a portion of an article in an article treatment zone. A plurality of articles are transported in single file through an article treatment zone. The articles may be glass containers, and the treatment material may be a metallorganic decorative spray. In the article treatment zone, mask means closely engage a portion of the article to shield or protect a portion of the article from contact by the treatment material. The mask means may take the form of counterrotating, complementary pairs of shield members which are cammed into engagement with the article at the treatment zone entrance, move in synchronism with the article through the treatment zone and are cammed out of engagement with the article at the exit of the treatment zone.

22 Claims, 7 Drawing Figures PATENTED JUH 3 1975 SHEET PATENTED JUP 3 I275 SHEET FIG. 5

lOIS? k FATENTEDJUH 3 I915 SHEET FIG. 6

FIG. 7

MOVING MASK FOR SHIELDING ARTICLES BACKGROUND OF THE INVENTION This invention generally relates to apparatus for shielding a portion of an article from treatment by a material applied to another portion of the article. More particularly, this invention relates to the shielding of moving articles in an article treatment zone. Most specifically, this invention relates to the shielding of moving articles in an article treatment zone by the engagement of the articles by counterrotating, complementary pairs of shield members.

It has been a problem in the area of the treatment of glass containers to shield the finish portion of the glass container from the influence of certain materials used for the treatment or decoration of glass containers. The finish portion is a relatively critical portion which must remain in the as formed state to ensure dimensional stability for subsequent capping operations. I have found that the finish portion may be most effectively shielded by the use of counterrotating complementary pairs of shield members which engage the glass container in the treatment area. This has proven more effective than the static shields or air barriers used in the prior art to shield the finish portion. By moving the shield members with the article being shielded, a more positive seal may be achieved than is possible with a fixed shield or an air barrier. An example of a moving shield in the prior art may be seen in U.S. Pat. No. 3,631,837.

SUMMARY OF THE INVENTION My invention is an apparatus for masking a portion of an article traveling in a substantially linear path through an article treatment zone. This apparatus is primarily made up of a mask means for shielding a portion of each individual article in the treatment zone to prevent treatment of the shielded portion of the article, a transport means, connected to the mask means, for moving the mask means with the articles, a frame means for supporting the transport means, and a drive means for moving the transport means in synchronism with the articles.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a top plan view of the apparatus of the present invention in a schematic form;

FIG. 2 is a perspective view of the apparatus of the present invention in its operational environment;

FIG. 3 is a side elevational view, on an enlarged scale, of a portion of the apparatus of FIG. I, with protective shrouds removed, as seen looking from the outside inwardly;

FIG. 4 is a cross-sectional view of a portion of the apparatus of FIG. 1 taken generally along the line 4-4;

FIG. 5 is a cross-sectional view taken generally along the line 5-5 in FIG. 3;

FIG. 6 is a cross-sectional view, on a somewhat enlarged scale, taken generally along the line 6-6 in FIG. 7; and

FIG. 7 is a top plan view, on a reduced scale, ofa portion of the apparatus as shown in FIG. 3.

DETAILED DESCRIPTION OF THE DRAWINGS The apparatus of the present invention is shown in a schematic form in FIG. 1 and shown generally in its operational environment in FIG. 2. FIGS. 1 and 2 will be described first to allow a general understanding of the operation of this apparatus. With specific reference to FIG. 2, the entrie apparatus is supported from a steel frame structure 10 which is placed on a suitable base, such as a floor. The mask means which moves in synchronism with a plurality of articles moving in a single file is shown in FIG. 2 as two counterrotating mask assemblies l2 and 14. The mak assemblies 12 and 14 are shown in FIG. 2 with a sheet metal shroud in place around them, as would normally be the case in operation, and the details of these assemblies will be shown in subsequent drawings. Within each of the mask assemblies l2 and 14, there are mounted four rotatably supported chain sprockets. The chain sprockets are at the extreme ends of the maks assemblies 12 and 14 and are mounted one above the other, such that two sprockets are mounted at each end of the mask assemblies l2 and 14. The sprockets are driven through a drive motor 16 which is attached to the frame structure 10. The drive motor 16 has attached to it a pulley or sprocket 18 which has trained about it an endless chain or belt 19 which is also trained about a second sprocket or pulley 20, attached to a shaft 22 connected to one pair of the sprockets within the mask assembly 12. Thus, rotation of the motor 16 will cause the drive shaft 22 to be driven. A third sprocket or pulley 24 is also mounted on the drive shaft 22. A fourth sprocket or pulley 26 is mounted on a shaft 28 which is connected to two of the sprockets contained within the mask assembly 14. An endless chain or belt 30 connects the sprockets 24 and 26. Thus, it may be appreciated that the two mask assemblies 12 and 14 are driven in synchronism through a drive means which may include the drive motor 16 and the sprockets 18, 20, 24 and 26 and the various chain members, such as 19 and 30. It would be possible to have the mask assemblies 12 and 14 driven through some other drive train which might be a drive train for articles which are to pass through or between the mask assemblies 12 and 14. As seen in FIG. 2, a plurality of articles are transported on a plurality of single file shafts 31. This particular transport mechanism does not form a part of the present invention, but rather may be any of a number of transport mechanisms which are well known in the prior art which will transport articles in single file while being suspended from jaws or various other holding means attached to the shafts 31. For the purposes of a specific illustration, the articles may be considered to be glass containers 32. It may be seen that the path of travel of the glass containers 32 being transported on the shafts 31 is between the two masking assemblies 12 and 14.

With specific reference now to FIG. 1, which is a schematic top view of the apparatus shown in FIG. 2, the operation of the mask assemblies 12 and 14 may be readily appreciated. It should be understood that in FIG. 1, the shrouds have been removed from the mask assemblies 12 and 14 and the structural details have been omitted for clarity and understanding the functioning of the apparatus. In FIG. 1, the movement of the glass containers 32 is in the direction indicated by the arrow. Each of the mask assemblies 12 and 14 have contained within it a plurality of mask means for shielding a portion of each individual glass container 32 in a treatment zone to prevent treatment of the shielded portion of the glass container 32. The mask means includes a plurality of pairs of shield members. The shield members for the mask assembly 12 are designated as 34, and the shield members for the mask assembly 14 are designated as 36. The mask means for mask assembly 12 is attached to an endless chain 38, or more properly a pair of endless chains 38A and 388, which is trained around rotatably mounted sprockets 40 and 40A. The mask means for the mask assembly 14 is attached to an endless chain 39, again, actually two chains, which is trained around rotatably mounted sprockets 41 and 41A. As pointed out previously, there are actually two pairs of sprockets in each mask assembly 12 or 14, but only two sprockets in each mask assembly l2 and 14 are shown in FIG. 1. The other of the pair of sprockets is below the sprockets shown in FIG. 1. It should be realized that the use of two pairs of sprockets and two endless chains for each mask assembly is primarily a matter of design practice. It is possible to use only one chain 38 and consequently one pair of sprockets 40 in each mask assembly, or other transport means could be provided to move the mask means in synchronism with the glass containers 32. As the glass containers 32 are directed between the two mask assemblies 12 and 14, an opening cam 42 mounted on the frame structure adjacent the mask assembly 12 forces the shield members 34 carried by the mask assembly 12 away from the path of travel of the glass containers 32. A corresponding opening cam 44 adjacent the mask assembly 14, and likewise carried by the frame structure 10, forces the shield members 36 away from the path of travel of the glass containers 32. This allows the glass containers 32 to enter between the corresponding shield members 34 and 36 without interference. Then, after the shield members 34 and 36 have been synchronized with the position of the glass container 32, the earns 42 and 44 come to an end. When the earns 42 and 44 end, the shield members 34 and 36 come together, as will be described in detail later, and encompass a portion of the glass container 32. After the shield member 34 and 36 have been closed, they protect or mask a portion of the glass container 32 from a treatment material which is applied in a treatment zone generally designated as Z. This material can be any of the many materials which are used to treat glass containers, for example metallorganic sprays which are used for decorative purposes. When such materials are applied to glass containers, it is usually necessary to protect the finish or closure accepting portion of the glass container from such materials. This is because the finish portion of the glass container 32 is a relatively critical portion, and application of some treatment materials to this portion will result in a malfunction of the closure after it is applied to the glass container 32. A holding cam 46 for the mask assembly 12 and a corresponding holding cam 47 for the mask assembly 14 maintain the shield members 34 and 36 in a closed position through the treatment zone Z. After leaving the treatment zone Z, the shield members 34 and 36 are engaged by opening cams 50 and 51, respectively on the mask assemblies 12 and 14. The opening cams 50 and 51 serve the same basic function as the open cams 42 and 44, in that they cause the shield members 34 and 36 to move away from the path of travel of the glass containers 32. This allows the shield members 34 and 36 to disengage themselves from the glass containers 32 as the glass containers 32 continue to move without striking or disrupting the travel of the glass containers 32. When the shield members 34 and 36 have completely left the influence of the glass containers 32, they are transported around the sprockets and continue on a path to be returned to the cams 42 and 44 to repeat the process with another series of glass containers 32. It will be noted that all of the shield members 34 and 35 contain a semicircular cutout portion 52, and 53 respectively. The semicircular cutout portion 52 meshes or mates with approximately onehalf of the finish portion of the glass container 32. The other half of the finish portion of the glass container 32 is covered by the complementary shield member 36 which likewise has the semicircular cutout 53 in it. Thus, the entire finish portion of the glass container 32 is enclosed or encompassed by the shield members 34 and 36 in the treatment zone Z.

With reference now to FIG. 3, the attachment of the shield member 34 to the chain 38 may be seen. It may now be clearly seen that there is an upper chain 38A and a lower chain 38B. The specific section illustrated in FIG. 3 is within the treating zone Z and is a view looking from inside the mask assembly 12 toward the treating zone 2. Some of the cams have been removed for clarity of illustration of the suspension of the shield member 34. It should be appreciated that the two mask assemblies 12 and 14 are substantially identical in construction and in the shield member 34 or 36 which they carry. The only true difference to be seen in these two assemblies 12 and 14 is that the shield members 34 rotate in a counterclockwise direction and the shield members 36 rotate in a clockwise direction. Aside from this, there is no structural difference, and the description of one should suffice for a description of the other. Two elongated pins 54 and 55 are connected between the upper chain 38A and the lower chain 38B. A support tube 56 is in sliding engagement on the pin 54..The support tube 56 is held in a fixed position with an upper locking collar 58 and a lower locking collar 59. The support tube 56 is relatively long and extends over a substantial portion of the pin 54. The pin 55 has a second sliding support tube 60 engaged over it. The support tube 60 is considerably shorter in overall length than the support tube 56. A tie bar 62 connects the tubes 56 and 60 as a unit. The manufacturing tolerances of this particular device make it difficult to precisely locate the elevation of the shield members 34 and 36 before assembly. Therefore, at the final assembly process, the locking collars 58 and 59 may be loosened and the support tube 56 moved up or down to position the shield members 34 and 36 at their precise location, so that both pairs match and are engaging the glass container 32 at the desired location. It should be realized that as the support tube 56 is moved up or down, the support tube 60 will be moved with it, since the two are tied together with the tie bar 62. When the proper elevation has been reached, the locking collars 58 and 59 are locked into position to hold the shield member 34 or 36 at its set elevation. The locking collars 58 and 59 may be the conventional set screw type locking collars.

FIG. 5 shows further details of the mounting of the shield members 34 and 36. In FIG. 5, it may readily be seen that the chain drive 39 for the mask assembly 14 is made up of two chains, an upper chain 39A and a lower chain 39B. In addition, it may be seen that a pin 64, connects the upper chain 39A and the lower chain 39B. The pin 64 corresponds in function to the pin 55 connecting the chains 38A and 388. A sliding support tube 65 is mounted on the pin 64. The sliding support tube 65 corresponds to the second sliding support tube 60 in function. Although not seen in FIG. 5, there is likewise a pin and sliding support tube connecting the chains 39A and 39B corresponding to the pin 54 and the tube 56 connecting the chains 38A and 38B. In a manner as was previously described with respect to the mask assembly 12, the support tube 65 is tied to its corresponding support tube with a tie bar 66. A carrier block 68 is attached to the support tube 56. A corresponding carrier block 69 is attached to the support tube 65. A mounting means for the shield members 34 and 36 is attached to the carrier blocks 68 and 69. In both cases, the mounting means is an elongated plate 70 and 72 respectively, made of a resilient material and suspended from the respective carrier blocks 68 and 69. The plate 70 is bolted to the carrier block 68 with a clamp plate 73 and a bolt 74. The plate 72 is attached to the carrier block 65 with a second clamp plate 76 and a bolt 77. The plates 70 and 72 are preferably made of a relatively thin stainless steel material which has good spring properties. FIG. 5 readily illustrates the cantilever mounting of the plates 70 and 72, and one may appreciate from this mounting that a considerable spring effect may be obtained near the lower portion of the plates 70 and 72 adjacent to the glass container 32. The remote end of the plates 70 and 72 terminate in a horizontal portion that is substantially perpendicular to the glass container and that extends substantially to the center line of the path of travel of the glass containers 32. These horizontal portions are respectively designated as 78 and 79. A transition portion of the plates 70 and 72 connect the horizontal portions 78 and 79 with the major vertical portion which is connected to the carrier blocks 68 and 69. Although not evident in FIG. 5, each of the horizontal portions 78 and 79 have a cutout portion adjacent to the peripheral edge of these portions and shaped to allow a portion of the glass container 32 to be engaged by the horizontal portions 78 and 79 without actually touching the glass container 32. These cutout portions may best be seen with reference to FIG. 7, where they are designated as 80 and 81.

The path of travel of the chains 38A and 38B is controlled by the use of cam followers 83 and 84, which are attached to the upper and lower ends of the pin 54. The cam followers 83 and 84 are respectively guided by an upper cam track 85 and a lower cam track 86. The upper cam track 85 is formed in an upper cam plate 88 and the lower cam track 84 is formed in a lower cam plate 89. The cam plates 88 and 89 are connected by a connecting column 90. While the pin corresponding to the pin 54 for the mask assembly 14 is not visible in FIG. 5, an upper cam follower 92 and a lower cam follower 93 are visible. These cam followers serve the same function as the cam followers 83 and 84 for the mask assembly 12 and are attached in the same manner as shown for the mask assembly 12. The cam followers 92 and 93 are respectively trapped in an upper cam track 95 and a lower cam track 96 which are formed in an upper cam plate 97 and a lower cam plate 98. The cam plates 97 and 98 are connected together as a unit with a connecting column 100. A horizontal cross member 102 supports the entire cam and chain assembly for the masking assembly 12 and is a part of the frame structure 10. Likewise, a corresponding horizontal cross member 103 serves the same function for the mask assembly 14, and is likewise a portion or is tied into the frame structure 10. Connected to the connecting column and depending downwardly and inwardly toward the path of travel of the glass containers 32 is a secondary shield support 105. A corresponding secondary shield support 106 is likewise connected to the connecting column 100. These secondary shield supports 105 and 106 terminate at their lower ends at a substantial distance away from the center line of the path of travel of the glass containers 32. Attached to the shield supports 105 and 106 are secondary shields 108 and 109 respectively. The secondary shields 108 and 109 bend inwardly at their lower ends toward the center line of the path of travel of the glass containers 32. The terminal point of the lower ends is at a point just sufficient to allow a glass container 32 of the maximum expected diameter to pass between these two plates. The secondary shield supports 105 and 106 and their respective secondary shields 108 and 109 extend only through the treatment zone Z. It is only in this area that it is necessary to protect the transport mechanism from contamination with the treatment material. An elongated pipe 110, which serves as one of a pair of manifold means, is attached to the secondary shield support 105 adjacent the point where the secondary shield 105 bends to direct itself inwardly toward the glass containers 32. The pipe 110 has a plurality of holes 1 11 drilled in it directed toward the glass containers 32. The pipe 110 extends substantially through the treatment zone Z and is capped at one end thereof. The other end of the pipe 110 is connected to a source of compressed gas, preferably compressed air. The compressed air is on continuously and blows through the holes 111 toward the glass container 32. A resilient seal member 112, connected to the secondary shield support 105 above the pipe 110, is forced into sealing engagement with the plate 70. Thus, the air, or other compressed gas which may be used, which exits through the holes 111 is forced downwardly between the plates 70 and the secondary shield 108 and must then exit downwardly along the glass container 32. This flow of compressed air provides another shielding mechanism and helps ensure absolute containment of the treatment material used in the treatment zone 2. The shield members 34 and 36 in theory should block any possible migration of the treatment material onto a finish portion, 113, of the glass container 32, but occasional irregularities in the configuratioon of the glass container 32 make it wise to provide this secondary source of shielding with the compressed air from the pipe 110. A complementary pipe 114, which serves as the second of the pair of manifold means, is mounted on the secondary shield support 106, containing a plurality of holes 1 15, again directed toward the glass container 32. A seal member 116 attached to the secondary shield support 106 above the pipe 114 again is in sealing engagement with the plate 72 and forces any compressed gas exiting from the holes 115 to sweep over the glass container 32. The pipe 114 may be connected to the same source of compressed gas as is the pipe 110, and is coextensive in length with the pipe 1 10.

While the spring forces off the plates 70 and 72 are normally sufficient to bring the shield members 34 and 36 into contact with the glass container 32 in their normal or rest position, a holding cam 118 mounted on the secondary shieldsupport 105 and a complementary holding cam 119 mounted on the secondary shield support 106 are used to maintain the shield members 34 and 36 in an absolutely closed position in the treatment zone Z. A holding cam follower 120 is mounted on the plate 70 and is engaged by the holding cam 118 to force the plate 70 inwardly toward the centerline of the path of travel of the glass containers 32. Likewise, a hold-ing cam follower 122 mounted on the plate 72 is engaged by the holding cam 119 and forces the shield member 36 toward the center line of the path of travel of the glass containers 32. Also seen in FIG. are the opening cam followers 124, mounted on the plate 70, and 125, mounted on the plate 72. As best illustrated in FIG. 4, the opening cam follower 124 is engaged by either the cam 50 or the cam 42, depending on its position in its path of travel. FIG. 4 illustrates engagement with the cam 50. When the cam 50 engages the opening cam follower 124, the shape of the cam 50 forces the plate 70 to be bent away from the center line of the path of travel of the glass containers 32, thus allowing the glass containers 32 to progress onward without any further influence from the shield member 34. It may be appreciated that this function is likewise performed by the cams 51 and 44 in cooperation with the opening cam follower 125 mounted on the plate 72. Since the cams 50 and 51 and 42 and 44 form complementary sets, these opening functions take place at the same time in the path of travel of the glass containers 32 and thus cause the shield members 34 and 36 to operate as a complementary unit or pair.

FIGS. 6 and 7 illustrate the details of the construction of the shield members 34 and 36. The shield member 34 is composed of the following parts: a retaining cover 128 has two horizontally extending flanges 129 and 130 connected to a top plate 131 by vertically extending walls. A rear vertical wall 132 is connected to the top plate 131 and seals the side of the retaining cover 128 away from the glass containers 32. The flanges 129 and 130 are riveted to the horizontal end portion 78 of the plate 70 with rivets 134. The rivets 134, as best seen in FIG. 6, extend below the portion 78 and may ride on the secondary shield member 108. This is done to ensure that the air from the holes 111 and the pipe 110 may wash over a portion of the glass container 32. However, this function is optional, and may be provided by proper alignment of the shield member 34 with the secondary shield member 108. The top plate 131 of the retaining cover 128 has a cutout portion which corresponds with the cutout portion 80 of the portion 78 of the plate member 70. Thus, in FIG. 7, the cutout portions lie one on top of the other and are identified by the general reference numeral 80. Again, keep in mind that this cutout portion 80 is designed to allow clearance of the glass container 32 when the two shield members 34 and 36 are brought together in contact. Carried within the retaining cover 128 is a seal block 136. The seal block 136 is preferably of a somewhat resilient material, for example Teflon, to allow some conformity to irregularities in the glass container 32. The seal block 136 itself is cut away on the face which faces the glass container 32 such that the cut away portion will engage the half of the glass container 32 which lies on the center line of the path of travel of the glass container 32 on the side of the shield member 34. In the specific example shown, the glass container 32 is symmetric on either side of the center line of its path of travel. However, this is not always necessarily the case, and the seal block 136 may be cut such that it would engage more or less than one-half of the actual circumference or peripheral area of the glass container 32. In such a ease, the seal block of the shield member 36 would engage or would be cut to engage the other portion of the glass container 32. The seal block 136 is retained within the retaining cover 128-with a spring 138. The spring 138 may be a wire-type spring which has a bent portion designed to engage corresponding notched portions 140 formed in the seal block 136. The spring force from the spring 138 on the seal block 136 holds the seal block 136 in a position which normally extends somewhat beyond the open edge of the retaining cover 128. Then, as the seal block 136 is brought into contact with the glass container 32, it is moved back slightly against the spring 138, thus holding it tightly in contact with the area of the glass container 32 which the seal block 136 is 'to protect. This resilient mounting of the seal block 136 also allows the seal block 136 to float and thus to conform to slight irregularities in the surface of the glass containers 32, or to conform to changes in the surface configuration of a glass container 32 if the glass container 32 were to be rotated within the tretment zone Z. The shield member 36 is constructed in an identical manner to that just described for the shield member 34. There is a second re taining cover 142 with flanges 143 and 144 riveted to the horizontal portion 79 of the plate 72 with rivets 145. A top plate 147 is connected to the flanges 143 and 144 by vertical wall, and is rear is sealed with a rear vertical wall 148. A second seal block 150 is restrained within the second retaining cover 142 with a spring 152. Again, a portion of the second seal block 150 is cut away to allow it to closely engage that portion of the glass container 32 which lies on the center line of the path of travel of the glass containers 32 on the side sealed by the shield member 36. Thus, when the two seal blocks 136 and 150 are brought into contact as a result of the movement of their respective support plates 70 and 72, a portion of the glass container 32 is closely engaged by the seal blocks 136 and 150 and the portion of the glass container 32 above the area engaged by the seal blocks 136 and 150 is thus protected from any material which might reach that area while the glass container is being treated in the treatment zone Z. In the specific example given, the two seal blocks 136 and 150 engage substantially the entire circumference of the glass container 32, or in the more general case, the entire perimeter of an article being shielded.

I claim:

1. Apparatus for masking a portion of articles which are traveling in a substantially linear path through an article treatment zone comprising, in combination:

mask means for shielding a portion of each individual article in said treatment zone to prevent treatment of the shielded portion of said article, said mask means including a plurality of complementary pairs of shield members, one of each pair being located on one side of the path of travel of said articles and the other of each pair being located on the opposite side of said path of travel;

transport means connected to said mask means moving said mask means with said traveling articles;

mounting means, connected to said shield members and said transport means, for supporting said shield members in a location movable toward and away from the path of travel of said articles. said mounting means comprising;

a plurality of complementary pairs of plate members made of resilient material, suspended from said transport means at one end thereof and having the opposite end thereof terminating in a horizontal portion substantially perpendicular to said article and extended substantially to the center line of the path of travel of said articles, said horizontal portion having a cutout portion extending from the peripheral edge of said horizontal portion and shaped to allow a portion of said article to be engaged by said horizontal portion without interference with the travel of said article; and

drive means for moving said transport means in synchronism with said articles.

2. The apparatus of claim 1, further including means for moving said mounting means toward said articles at the entrance to said article treatment zone.

3. The apparatus of claim 2, wherein said means for moving said mounting means toward said articles comprises:

an opening cam follower for each of said shield members attached to said mounting means; and

at least two cams, mounted on opposite sides of the path of travel of said articles, shaped to engage said opening cam followers and guide said shield members into engagement with said articles.

4. The apparatus of claim 1 further including means for moving said mounting means away from said articles at the exit from said article treatment zone.

5. The apparatus of claim 4, wherein said means fro moving said mounting means away from said articles comprises:

an opening cam follower for each of said shield members attached to said mounting means; and

at least two cams, mounted on opposite sides of the path of travel of said articles, shpaed to engage said opening cam followers and guide said shield members away from engagement with said articles.

6. The apparatus of claim 1, wherein said shield members include, a retaining cover, attached to said horizontal portion of said mounting means and having a cutout portion conforming to the cutout portion of said horizontal portion of said mounting means, said retaining cover being open on the side facing said articles and closed on the side remote from said articles.

7. The apparatus of claim 6, wherein said shield members further include, a seal block contained within said retaining cover, said seal block having a cutout portion generally conforming to the shape of the portion of said articles extending beyond the center line of the path of travel of said articles on the side of said center line on which said seal block is positioned.

8. The apparatus of claim 7, wherein said shield members further include, spring means for resiliently holding said seal block in said retaining cover.

9. The apparatus of claim 1, wherein said transport means comprises, a pair of counterrotating chain and sprocket means, one of said pair of chain and sprocket means being located on each side of the path of travel of said articles.

10. The apparatus of claim 9, wherein said chain and sprocket means includes:

at least one pair of rotatably mounted driven sprockets, connected to said drive means, one driven sprocket of said pair being mounted on one side of the pathof travel of said articles and the other one of said pair of driven sprockets being mounted on the opposite side thereof; v at least one pair of rotatably mounted idler sprockets,

longitudinally spaced apart from said driven sprockets a distance at least equal to the length of said treatment zone, one sprocket of said idler pair of sprockets being mounted on one side of the path of travel of said articles, and the other one of said pair of idler sprockets being mounted on the opposite side' thereof; and

pair of endless chains, one of said pair of endless chains being trained around the driven sprocket and idler sprocket on one side of the path of travel of said articles and the other of said pair of endless chains being trained around the driven and idler sprockets on the opposite side of the path of travel of said articles.

11. The apparatus of claim 1, further including means for holding said complementary pairs of shield members in engagement with said articles in said treatment zone.

12. The apparatus of claim 11, wherein said means for holding said shield members in engagement with said articles includes:

a holding cam follower attached to said mounting means on the face of said mounting means opposite said articles; and

at least two cams, mounted on opposite sides of the path of travel of said articles, shaped to engage said holding cam followers and hold said shield members in engagement with said articles in said treatment zone.

13. The apparatus of claim 1, further including:

a pair of secondary shields extending substantially the entrie length of said treatment zone and extending from both sides of the center line of the path of travel of said articles toward said center line and terminating at a location on both sides of said center line such that said articles may pass between said secondary shields without contact therewith, said secondary shields being located in a position between said mask means and the portion of said article being treated.

14. The apparatus of claim 13, further including means for creating a flow of gas toward the portion of said article being treated, said gas flow emanating from the direction of said secondary shields on both sides of the center line of the path of travel of said articles in a direction toward the portion of said articles being treated.

15. The apparatus of claim 14, wherein said means for creating a flow of gas includes:

a pair of manifold means, one of said manifold means being located on each side of the center line of the path of travel of said article, said manifold means being substantially coextensive with said treatment zone, said manifold means each having one end thereof closed and the opposite end open, each of said manifold means having a plurality of openings formed therein along the length thereof and directed toward said articles in the space defined by said mask means and said secondary shields; and

a source of gas under pressure connected to the open end of each of said manifold means.

16. In an apparatus of the type wherein a plurality of articles are transported in a single file through a treatment area, wherein a portion of said articles is coated in said treatment area with a treatment material, and another portion of said articles is not coated, the improvement in said apparatus which comprises:

mask means, moving in synchronism with said articles, for individually shielding the portion of said articles that is to remain uncoated in said treatment area, said mask means including a plurality of complementary pairs of shield members, one of each pair being located on one side of the path of travel of said articles and the other of each pair being located on the opposite side of said path of travel;

transport means, connected to said mask means, for

moving said mask means with said articles;

mounting means, connected to said shield members and said transport means, for supporting said shield members in a location movable toward and away from the path of travel of said articles, said mounting means comprising:

a plurality of complementary pairs of plate members made of resilient material, suspended from said transport means at one end thereof and having the opposite end thereof terminating in a horizontal portion substantially perpendicular to said article and extended substantially to the center line of the path of travel of said articles, said horizontal portion having a cutout portion extending from the peripheral edge of said horizontal portion and shaped to allow a portion of said article to be engaged by said horizontal portion without interference with the travel of said article;

and drive means for moving said transport means in synchronism with said articles.

17. The apparatus of claim 16, further including means for moving mounting means toward said articles at the entrance to said article treatment zone.

18. The apparatus of claim 16, further including means for moving said mounting means away from said articles at the exit from said article treatment zone.

19. The apparatus of claim 16, further including means for holding said complementary pairs of shield members in engagement with said articles in said treatment zone.

20. The improvement of claim 16, further including:

a pair of secondary shields extending substantially the entire length of said treatment zone and extending from both sides of the center line of the path of travel of said articles toward said center line and terminating at a location on both sides of said center line such that said articles may pass between said secondary shields without contact therewith, said secondary shields being located in a position between said mask means and the portion of said article being treated.

21. The apparatus of claim 20, further including means for creating a flow of gas toward the portion of said article being treated, said gas flow emanating from the direction of said secondary shields on both sides of the center line of the path of the travel of said articles in a direction toward the portion of said articles being treated.

22. The apparatus of claim 16, wherein said transport means comprises, a pair of counterrotating chain and sprocket means, one of said pair of chain and sprocket means being located on each side of the path of travel 

1. Apparatus for masking a portion of articles which are traveling in a substantially linear path through an article treatment zone comprising, in combination: mask means for shielding a portion of each individual article in said treatment zone to prevent treatment of the shielded portion of said article, said mask means including a plurality of complementary pairs of shield members, one of each pair being located on one side of the path of travel of said articles and the other of each pair being located on the opposite side of said path of travel; transport means connected to said mask means for moving said mask means with said traveling articles; mounting means, connected to said shield members and said transport means, for supporting said shield members in a location movable toward and away from the path of travel of said articles, said mounting means comprising; a plurality of complementary pairs of plate members made of resilient material, suspended from said transport means at one end thereof and having the opposite end thereof terminating in a horizontal portion substantially perpendicular to said article and extended substantially to the center line of the path of travel of said articles, said horizontal portion having a cutout portion extending from the peripheral edge of said horizontal portion and shaped to allow a portion of said article to be engaged by said horizontal portion without interference with the travel of said article; and drive means for moving said transport means in synchronism with said articles.
 1. Apparatus for masking a portion of articles which are traveling in a substantially linear path through an article treatment zone comprising, in combination: mask means for shielding a portion of each individual article in said treatment zone to prevent treatment of the shielded portion of said article, said mask means including a plurality of complementary pairs of shield members, one of each pair being located on one side of the path of travel of said articles and the other of each pair being located on the opposite side of said path of travel; transport means connected to said mask means for moving said mask means with said traveling articles; mounting means, connected to said shield members and said transport means, for supporting said shield members in a location movable toward and away from the path of travel of said articles, said mounting means comprising; a plurality of complementary pairs of plate members made of resilient material, suspended from said transport means at one end thereof and having the opposite end thereof terminating in a horizontal portion substantially perpendicular to said article and extended substantially to the center line of the path of travel of said articles, said horizontal portion having a cutout portion extending from the peripheral edge of said horizontal portion and shaped to allow a portion of said article to be engaged by said horizontal portion without interference with the travel of said article; and drive means for moving said transport means in synchronism with said articles.
 2. The apparatus of claim 1, further including means for moving said mounting means toward said articles at the entrance to said article treatment zone.
 3. The apparatus of claim 2, wherein said means for moving said mounting means toward said articles comprises: an opening cam follower for each of said shield members attached to said mounting means; and at least two cams, mounted on opposite sides of the path of travel of said articles, shaped to engage said opening cam followers and guide said shield members into engagement with said articles.
 4. The apparatus of claim 1 further including means for moving said mounting means away from said articles at the exit from said article treatment zone.
 5. The apparatus of claim 4, wherein said means fro moving said mounting means away from said articles comprises: an opening cam follower for each of said shield members attached to said mounting means; and at least two cams, mounted on opposite sides of the path of travel of said articles, shpaed to engage said opening cam followers and guide said shield members away from engagement with said articles.
 6. The apparatus of claim 1, wherein said shield members include, a retaining cover, attached to said horizontal portion of said mounting means and having a cutout portion conforming to the cutout portion of said horizontal portion of said mounting means, said retaining cover being open on the side facing said articles and closed on the side remote from said articles.
 7. The apparatus of claim 6, wherein said shield members further include, a seal block contained within said retaining cover, said seal block having a cutout portion generally conforming to the shape of the portion of said articles exTending beyond the center line of the path of travel of said articles on the side of said center line on which said seal block is positioned.
 8. The apparatus of claim 7, wherein said shield members further include, spring means for resiliently holding said seal block in said retaining cover.
 9. The apparatus of claim 1, wherein said transport means comprises, a pair of counterrotating chain and sprocket means, one of said pair of chain and sprocket means being located on each side of the path of travel of said articles.
 10. The apparatus of claim 9, wherein said chain and sprocket means includes: at least one pair of rotatably mounted driven sprockets, connected to said drive means, one driven sprocket of said pair being mounted on one side of the path of travel of said articles and the other one of said pair of driven sprockets being mounted on the opposite side thereof; at least one pair of rotatably mounted idler sprockets, longitudinally spaced apart from said driven sprockets a distance at least equal to the length of said treatment zone, one sprocket of said idler pair of sprockets being mounted on one side of the path of travel of said articles, and the other one of said pair of idler sprockets being mounted on the opposite side thereof; and a pair of endless chains, one of said pair of endless chains being trained around the driven sprocket and idler sprocket on one side of the path of travel of said articles and the other of said pair of endless chains being trained around the driven and idler sprockets on the opposite side of the path of travel of said articles.
 11. The apparatus of claim 1, further including means for holding said complementary pairs of shield members in engagement with said articles in said treatment zone.
 12. The apparatus of claim 11, wherein said means for holding said shield members in engagement with said articles includes: a holding cam follower attached to said mounting means on the face of said mounting means opposite said articles; and at least two cams, mounted on opposite sides of the path of travel of said articles, shaped to engage said holding cam followers and hold said shield members in engagement with said articles in said treatment zone.
 13. The apparatus of claim 1, further including: a pair of secondary shields extending substantially the entrie length of said treatment zone and extending from both sides of the center line of the path of travel of said articles toward said center line and terminating at a location on both sides of said center line such that said articles may pass between said secondary shields without contact therewith, said secondary shields being located in a position between said mask means and the portion of said article being treated.
 14. The apparatus of claim 13, further including means for creating a flow of gas toward the portion of said article being treated, said gas flow emanating from the direction of said secondary shields on both sides of the center line of the path of travel of said articles in a direction toward the portion of said articles being treated.
 15. The apparatus of claim 14, wherein said means for creating a flow of gas includes: a pair of manifold means, one of said manifold means being located on each side of the center line of the path of travel of said article, said manifold means being substantially coextensive with said treatment zone, said manifold means each having one end thereof closed and the opposite end open, each of said manifold means having a plurality of openings formed therein along the length thereof and directed toward said articles in the space defined by said mask means and said secondary shields; and a source of gas under pressure connected to the open end of each of said manifold means.
 16. In an apparatus of the type wherein a plurality of articles are transported in a single file through a treatment area, wherein a portion of said articles is coated in said treatment area with a treatment material, and another portion of said articles is not coated, the improvement in said apparatus which comprises: mask means, moving in synchronism with said articles, for individually shielding the portion of said articles that is to remain uncoated in said treatment area, said mask means including a plurality of complementary pairs of shield members, one of each pair being located on one side of the path of travel of said articles and the other of each pair being located on the opposite side of said path of travel; transport means, connected to said mask means, for moving said mask means with said articles; mounting means, connected to said shield members and said transport means, for supporting said shield members in a location movable toward and away from the path of travel of said articles, said mounting means comprising: a plurality of complementary pairs of plate members made of resilient material, suspended from said transport means at one end thereof and having the opposite end thereof terminating in a horizontal portion substantially perpendicular to said article and extended substantially to the center line of the path of travel of said articles, said horizontal portion having a cutout portion extending from the peripheral edge of said horizontal portion and shaped to allow a portion of said article to be engaged by said horizontal portion without interference with the travel of said article; and drive means for moving said transport means in synchronism with said articles.
 17. The apparatus of claim 16, further including means for moving mounting means toward said articles at the entrance to said article treatment zone.
 18. The apparatus of claim 16, further including means for moving said mounting means away from said articles at the exit from said article treatment zone.
 19. The apparatus of claim 16, further including means for holding said complementary pairs of shield members in engagement with said articles in said treatment zone.
 20. The improvement of claim 16, further including: a pair of secondary shields extending substantially the entire length of said treatment zone and extending from both sides of the center line of the path of travel of said articles toward said center line and terminating at a location on both sides of said center line such that said articles may pass between said secondary shields without contact therewith, said secondary shields being located in a position between said mask means and the portion of said article being treated.
 21. The apparatus of claim 20, further including means for creating a flow of gas toward the portion of said article being treated, said gas flow emanating from the direction of said secondary shields on both sides of the center line of the path of the travel of said articles in a direction toward the portion of said articles being treated. 